Without wishing to constrict the technology field which concerns this invention, it may be helpful to delineate that Class 141, directed to fluent material handling, with receiver or receiver contacting mean, contains Subclass 286 which reads on technology with a multiple passage filling means for diverse materials with baffle, spreader, displacer, drip ring filter or screen. In addition, Subclass 392 relates to miscellaneous fluent material handling contacting means, such as filling heads. In Class 222, which relates to dispensing, Subclass 566 concerns nozzles, spouts and pouring devices. These particular subclasses may be among many subclasses which are pertinent to the background of this invention. References classified in the above subclasses pertinent to this invention include McLennand, U.S. Pat. No. 3,805,856; Waxlax, U.S. Pat. No. 3,698,452; and Voss, U.S. Pat. No. 3,838,798.
In Waxlax, the problem of foam interference within a filling of a bottle is overcome by a vertical filling tube having a porous nozzle adapted to be inserted to the vessel to be filled. Liquid is then discharged from the side of the nozzle in extremely fine streams. This nozzle is formed of powdered metal or ceramic materials. In McLennand, a nozzle is provided, which is porous, for discharging foamable material to a similar closed container. The end of the nozzle comprises two annular evenly spaced screens separated apart by two struts. The porous walls of the screens are formed from cylindrical screens of extremely fine mesh (such as 50 to 100 microns) to provide a double porous wall with a slight spacing therebetween to reduce the velocity of the liquid and change the pattern of flow to become smoother and to direct the flow downwardly. The pressure forcing the fluid through the perforated nozzle is increased without problems of foam formation.
In Voss, aluminum killed steels are poured through a specially constructed nozzle, without problems of aluminum slag formation, by providing a blanket of an inert gas about the inside surface of the bore of the nozzle. The blanket of inert gas also prevents nozzle erosion. These references, even in their combination, fail to address the problem of foaming in a diesel fuel tank and also fail to provide a simple mechanical apparatus for elimination of undesirable foaming.